Field of Invention
The present invention relates to a photosensitive resin composition and its application thereof. More particularly, the present invention relates to a film formed by the photosensitive resin composition and its application thereof. The film has a good refractivity and adhesivity to molybdenum (Mo).
Description of Related Art
In the manufacturing process of a liquid crystal display component, forming a protective film on a substrate is an important step. Demanding procedures under harsh conditions are required for manufacturing a liquid crystal display component or a solid-state imaging device, etc. For example, local high temperature occurs when processing by infusion with an acid solvent or alkaline solvent on the surface of substrate or by sputtering to form a wiring electrode layer. Thus, the protective film is laid on these components to prevent them from damage. Nowadays, the protective film is generally formed on the substrate by subjecting a photosensitive resin to processes of coating, exposure and developing, etc.
To enable the protective film to resist the aforementioned harsh conditions of the processes, high transparency, high surface hardness and smoothness are required, along with an excellent adhesivity between the protective film and substrate. Moreover, good resistance to water, solvents, acid, alkali and the like of the protective film is also required. In the aforementioned characteristics, since the protective film is formed on a color filter or a substrate, the requirement of high transparency is critical. If the transparency of the protective film is poor, when the protective film is applied to the liquid crystal display element, the brightness of the liquid crystal display element is insufficient, and the display quality of the liquid crystal display element is impacted.
To improve the transparency of the protective film, Japanese Patent Publication No. 2010-054561 disclosed a photosensitive composition for a protective film, comprising: an alkali-soluble bonding resin (A), a compound having a vinyl unsaturated group (B), a photoinitiator (C), and a solvent (D), in which the bonding equivalence of the unsaturated bond in the compound having a vinyl unsaturated group (B) is between 90 and 450 g/eq, and the amount of unsaturated double bond of a single compound is between 2 and 4 in the compound having a vinyl unsaturated group (B). A weight average molecular weight of the alkali-soluble bonding resin (A) is between 10,000 and 20,000.
Additionally, Japanese Patent Publication No. 2004-240241 has disclosed a photosensitive composition comprising: a copolymer (A), a polymer having a vinyl unsaturated group (B) and a photoinitiator (C). The copolymer (A) is polymerized by an unsaturated carboxyl (anhydride) having a vinyl group, a compound having a vinyl unsaturated group containing an epoxy group and other compounds having a vinyl unsaturated group. The photoinitiator (C) is 2-butanedione-[-4-methylthio benzene]-2-(O-oxime acetate), 1,2-butanedione-1-(-4-morpholino phenyl)-2-(O-benzoyl oxime), 1,2-octadione-1-[4-thiophenyl benzene]-2[O-(4-methyl benzoyl) oxime] or the like. However, the film formed by the photosensitive resin composition is unable to satisfy increasing requirements of refractivity and adhesivity to molybdenum.
Therefore, how to achieve the requirements of the refractivity and the adhesivity to molybdenum at the same time is a goal in the technical field of the present invention.